The image recording devices include X-ray imaging systems of various types, from a simple through-illumination system through angiographic devices to computer tomographs. The image recording devices include also PET devices (where PET stands for positron emission tomography) and SPECT devices (where SPECT stands for single photon emission computer tomography). Medical devices of the generic type mentioned in the introduction can also include magnetic resonance devices. The device can also work with ultrasound. Finally, optical endoscopes and equipment for optical coherence tomography also belong with the devices cited above. When the above medical device is designed as a therapeutic device, it may incorporate a linear accelerator or proton therapy equipment.
Medical devices of the generic type cited are normally so large that the patient is brought to the device, and not the device to the patient. Frequently, the medical device fills the treatment room into which the patient is brought. With the help of an imaging device it is possible to obtain pictures of bones, vessels and organs. When designed as a therapeutic device, treatment is carried out on the patient. In both cases it is generally important that a reliable diagnosis can be made for the patient, that is the patient's illness or injury, as applicable, can be clearly identified. Frequently, the making of a diagnosis requires an analysis of bodily fluids. This is usually carried out somewhere away from the medical device. In a hospital environment, the bodily fluid is taken, for example, to a separate hospital laboratory, there it is analyzed and the result is reported back. In particular in the case of emergency patients, this is a bad thing, because time is lost due to the long distances and the awkwardness of the procedure.
The publication US 2005/0153379 A1 describes a measuring probe with which an analytical chip can be introduced into a patient's bloodstream. Using such a measuring probe, the in vivo detection of tumor cells and similar biological markers is possible. The concentration of the biological markers, measured using the chip, can be read out via the probe and shown on a display device. Instead of a chip, the measuring probe can also have two glass fibers, where light is conducted to the tip of the measuring probe via one of the glass fibers and the light reflected by the bodily fluids is fed back via the second glass fiber. Using a spectral analysis of the reflected light, it is again possible to draw conclusions about the presence of certain biological markers.